The present invention relates to light projectors that produce light beams for specialty lighting effects. More particularly, the present invention pertains to light projectors that can produce light beams of selected cross-sectional contours, or profiles, and apparatus for mounting and installing such projectors.
Specialty light projectors are known for use in illuminating objects and scenes. Such light projectors may be used in lighting landscape features, architectural features, items displayed in cabinets or the like, art works, including pictures and sculpture, and scenes on a theatrical stage. Various techniques may be employed to affect a projected light beam, selectively blocking, or masking, a portion of the beam.
A mask, or masking device, is placed in the path of the light beam as a field stop, between condensing lenses and objective lenses, to define the cross-sectional profile of the light beam. A circular aperture may be used to define a circular profile for a projected light beam, but structured profiles may be achieved with more elaborate field stops, or masking devices, to produce desired specialty lighting effects. For example, a four-blade shutter is known for providing varied shapes defined by the straight edges of the blades. Such a shutter blade system typically has a handle, or tab, protruding from the outer edge of each blade so that the blades may be adjusted individually. However, when the only access to the light projector is from above, the tab of the bottom shutter blade may be inaccessible, and therefore adjustment of the light beam profile in that regard may be impractical, if not impossible. Also, one or more holes of any desired shape may be cut in a slide, or plate, which then serves as a masking device.
Additionally, a masking device may be made by using the light projector as a camera, with photosensitive material located where a masking device would be placed. With the light projector in its intended position relative to the target to be illuminated, the photosensitive material is exposed to light reflected from the target into the light projector. A negative photograph of the object to be illuminated by the projector, the target, is thus taken. U.S. Pat. No. 4,217,047 discloses apparatus for obtaining such a photograph. A photographic cassette or a self-developing film pack may be used. A photographic shutter may be added to the projector to control the entrance of light into the projector from the target. The photographic image of the target thus obtained is superimposed on a metal sheet and a hole is then cut in the sheet along the outline of the target image in the photograph. The metal sheet is then used as a mask, having an aperture that conforms in contour to the contour of the photographic image of the target. Alternatively, a metal sheet mask blank is painted and then coated with a photosensitive emulsion layer. The coated mask blank is used as film, which is then developed to obtain a photographic image of the target. An aperture stop may be used to control the amount of light that enters the projector from the target to expose the photosensitive emulsion. The metal sheet is then cut with a knife along the contour of the photographic image of the target to produce a masking device with an aperture that has the same contour as the target.
Contour light projectors may be installed in a variety of ways, depending on the environment and the manner of use. For example, a light projector may be held on a bracket or the like, with the bracket fixed to a wall or other structure. A light projector may be installed above a ceiling to project a light beam down toward the floor, or at an angle toward an object or toward a portion of a wall. Generally, an above-the-ceiling installation involves locating the light projector within a housing that is placed above the level of the ceiling. Access from above the ceiling may or may not be available to install the housing and light projector, or to service the light projector after installation is completed. Further, the light projector must still be mounted within the housing, and the manner of so mounting the light projector will determine the limits of one""s ability to direct the projected light beam, and to service the light projector in general.
It is advantageous and desirable to provide improved specialty lighting systems with mounting assemblies that include greater flexibility in mounting and directing light projectors, housings that are more adaptable to installation circumstances, masking devices that are easier to use and more effective, and light projectors with improved construction. The present invention provides contour lighting systems with a versatile mounting assembly, convenient and practical housings, improved masking devices, and improved light projector construction.
The present invention provides a lighting system including a contour light projector, masking devices for the light projector, a mounting assembly, and system housings for installation in various architectural settings. The mounting assembly includes a frame having an annular flange, and may also include a saddle having a cross member and a seat on which the light projector is selectively mounted, and a dual pivot system provided by the frame and the saddle whereby two pivot axes may be established such that the saddle may pivot about either axis relative to the frame to so orient the light projector. A light projector according to the present invention provides an optical bench within a housing assembly of the light projector on which one or more clamps are positioned to hold optical devices such as a lamp and a condensing lens of the projector. An improved shutter blade mask includes concave edges on the blades to define the contour of the light beam produced by the light projector, and a shutter blade that has two tabs, extending laterally from the blade rather than a single tab extending from the outer edge of the blade. Another mask comprises a glass plate having affixed thereto a photosensitized tape that is exposed to light and developed, and in which an opening is made to determine the contour of the light beam in the light projector. Lighting system housings include an enclosure that is closed on the bottom by a plate featuring a light projection hole, and spring hangers by which the plate is suspended.